DESCRIPTION: (Applicant's Description) We propose pilot and developmental studies on the use of clinical data to study the health effects of marijuana use. Specifically, we will assess the feasibility of studying cancer risk based upon information regarding marijuana use that have been collected routinely from patients entering Roswell Park Cancer Institute (RPCI) since 1982. These data require matching to medical record and tumor registry data, evaluation of response rates and completeness, and classification by disease and patient birth cohort and sex. We will evaluate the utility of these data for case-control studies for the purposes of replicating recent reports by others of risk for certain cancer types in certain patients as well as the presence or absence of risk for other sites. Initial investigation will focus on prostate and cervical cancer. Subsequent studies will examine effects in other major tumor types including lung, colorectal, ovary and breast cancers. To better understand the interaction of risk factors and exposures in patients at risk of cancer we will examine correlation among exposure variables across the entire population studied. We also will conduct quality control assessments of the data to determine the reproducibility of marijuana exposure data collected by the means we have employed. Once these developmental steps are accomplished, this analytic database can be used to explore new hypotheses, validate the findings of others, and examine interactions of risks not heretofore possible. It is also possible that it can be the basis for future multidisciplinary efforts that link biological and/or molecular markers to the defined epidemiologic resource. Because of the developmental nature of the activities and the PI and sponsoring institution's limited prior experience in drug abuse research, this application is made under the Small Grants Program.